Circuit breaker



MM M. J. @Mmmm Mmmm@ CIRCUIT BREAKER Filed Oct. ll', 1934 5 Sheets-Sham:l

l 1 -rs WK l a l INVENTOR CIRCUIT BREAKER Filed Oct. ll, 1934 3Sheets-Sheet 2 WlTNEssEs gay/@ yp11-il 28, 1936., H. J. @NAES CIRCUITBREAKER Filed Oct. ll, 1934 .3 SheetSf-Sheel 3 ITNESSES; INVENTOR/ff//Jf u., BY f ATTORN Y atente prm B, il

Herbert Il', abba, Wi

lab., Wm assigner to Westinghouse Electric d: Manufacturing @ompany,hast Pittsburgh, lia., a corporation oi Perlmutt Application etober lll,liti, aerial lilo.. itllpti id mais. (hi. titi ll/ly invention relatesto electrical switching equipment and. particularly to outdoordisconnecting switches for use with moderate and highvoltagetransmission circuits.

Dlsconnecting switches of this type are ordinarily used for isolating orsectionalizlng portions of a distribution circuit, and their designpresents a rather complex problem to the electrical art. Usually suchswitches are mounted outdoors and are, therefore, subjected to verysevere weather conditions, especially inthe northern States due to iceand sleet formation. in ordinary service, the switches are operatedcomparatively infrequently, and this, in combination with their normalexposed condition provides an almost ideal condition for oxide andcorrosion formation.

in theinterests of safety, the switches must include means forpositively locking the blades in the 'closed-ircuit position, in orderthat the blades shall notobe blown open by the magnetic forces incidentto abnormal overload conditions. Further, they must be capaple ofreliable operation underthe most adverse conditions without undulystraining the supporting or actuating lnsulators. And lastly, to preventwelding of the contacts and undesirable heating of the cooperatingcontact parts, the contact mechanism must include means for cuttingthrough corrosion during the circuitclosng operation.

in contrast to these enacting operational requlrements, commerciallysuccessful switches must be simple in design to facilitate maintenanceworlr and must be comparatively low in cost, due to the large numberswhich are used on even a small system. Ii/lost of the prior art deviceshave had to effect a compromise between operational characteristics andcost, and iew of them have been entirely satisfactory. ln my copendlngapplications, Serial Nos. 697,6ll, 697,612 and 727,7i6, l1 havedisclosed a switch which satisfactorily meets most ofthe aboveenumerated reduirements. Even this switch, however, has certainundesirable features and the principal object of the present inventionis the overcoming of these dmculties.

The disconnecting switch of my invention pref-- erably utilizes a bladestructure which includes vtwo (or more) blade members, at least one ofwhich is movable relative to the other, a means for securing highcontact pressure between the cooperating contact surfaces of the bladeandv contact means during the circuit closing operation, and a switchactuating means which, during the switch closing operation. successivelyswings the blade structure into proidmity with the cooperating contactmeans and then moves one of the blade members relative to the other inorder to actuate the contact pressure securing means This arrangementmaires possiblea simple and 5 comparatively inexpensive switch which iseirtremely reliable in operation. Iihe contacts may be caused to engagewith a wiping action, and by proper design of the operating mechanism,the stresses induced in the operating member may be 10 reduced to a verysmall magnitude. Further, it

is a sple matter, as pointed out in application Serial No. 727,lt6, toprovide a switch of this type with means for rigidly connecting thespaced insulators in order to prevent the inducing of large iscantilever stresses in either of those insulators when the switch isbeing moved to either the open or the closed circuit position None ofthe previously developed switches of this multiple blade type have beenprovided with 2e means for positively controlling the movement of theblade assemblage during the circuit closing operation. in the verticalbrealr switches (shown in applications ilerial rios. ttilm and'l2'l,'li6) this is not important, since the force of all gravity would,in most instances, bias the blade members so as to assure that thecircuit closing operation would taire place in two successive steps. inthe side brealr and in certain applications of the vertical brealrstructures, however, to it has been found desirable to provide a springor other means for biasing the blade elements toward the open circuitposition in order to assure that the normal successive operation shalltaire place. auch arangements, however, do not posi- 35 tively determinethe relative positionsiof the movable elements of the switch during imoperation, and ii the blade assemblage strikes an obstruction, duringthe switch closing movement, the movable elements which actuate thecontact le pressure securing means will be moved relative to one anotherand will thereby prevent the blade means from engaging the cooperatingcontacts. 'in the present invention one linlrage is utilized forswinging the bladev assemblage from one podo because of prematureoperation of the contact pressure securing means.

This linkage arrangement is applicable to other forms of switches andlike equipment, and afurther object of my invention is to provide anlmproved actuating mechanism for use with electrical switches andsimilar devices generally.

Another object of my invention is to provide an improved, simplifiedvoperating mechanism which shall be capable of effecting the actuation ofthe controlled equipment in two successive steps, while at the same timepermitting the use of a rotatable actuating member which moves at asubstantially constant speed.

A further object of my invention is to provide an actuating mechanismfor a multiple blade switch which shall include means for swinging thebladeassemblage from one position to the other and for moving one of theblade members relative to the blade assemblage, the two movements totake place in successive steps regardless of the position oi.' theswitch.

These and other objects of my invention will be made more apparent byreference to the following drawings and description, wherein I haveparticularly set forth the structural features of a preferred embodimentof my invention. Refer- -ring to the drawings,

Figure 1 is a side elevational view of a vertical brake disconnectingswitch wherein are embodied the principal features oi' my invention,

Fig, 2 is a plan view of the switch shown in Fig. 1,

' Fig. 3 is a fragmentary elevational view of the switch shown in Figs.1 and 2, showing the relative position of the several elements duringthe initial stages of the switch opening operation,

Fig. 4 is a view similar to Fig. 3, showing the --position of the switchelements shortlyv before the blade has been moved to the fully openposition,

Figs. 5, 6, and 'I are fragmentary perspective views showing varioussteps in the switch opening operation, and

Fig. B is a fragmentary plan view showing certainof the details of theswitch operating mechanism.

The preferred embodiment of my invention illustrated in the drawings isof the three-insulator, vertical break type. It includes a channel ironbase I, a pair of spaced insulators 3 and 5 rigidly supported upon thebase I, and a third insulator 1 rotatably supported upon the base,through a bearing 9, in order to permit the actuation of the switch. Ametallic cap II is cemented to the top of each of the three insulators.A jaw member I3 is supported upon the cap II of the left-hand (Figs. 5and 6) insulator 3; a cast double-crank member I5 is affixed to the capmember of the rotatable insulator 1, and the `blade assemblage I1 ispivotally supported upon a U-shaped support member I9 ailixed to the capof the other stationary insulator 5.

The jaw contact I3 comprises a fiat central portion 2| for engaging thecooperating cap member II, and a pair of upstanding side members 23,which have flared outer ends ingorder to facilitate the engagement ofthe blade assemblage with the jaw contact. The inner contact surfaces ofone of the upstanding side members terminates in a toothed portion 25,which is adapted to cooperate with the blade means I1 in order to permitthe mechanical inter-connecting `of vthe insulators 3 and V5 during theoperation of the switch, and the inner contactsurface 21 of the othermember-,23 is machined to an arcuate form in order that it may engagethe cooperating portion of the blade means with a high pressure linecontact."The central portion 2l of the jaw terminates in a projectingsection 29', cast integral therewith, which serves to support one of thetwo switch terminals 3|.

The blade assemblage I1 comprises a pair of tubular blade members 33 and35 which are joined together adjacent their outer end by a linkage,which comprises two parallel link members 31, one end of' which linkageis pivotally joined to each of the blade members. At their inner end,the blade members are joined together by a second linkage, whichcomprises two similar link members 39, and thus take the form of aquadrilateral linkage. The outer end of each of the blade members isprovided with a contact portion 4I', the one which is aiiixed to theinner blade member 39 having a toothed section 43 for cooperating withthe toothed vportion 25 of the jaw I3, and the other contact portionbeing formed with a substantially flat contact ysurface 45 forcooperating with the other jaw contact portion 21.

A Y-shaped support member 41 is brazed or otherwise rigidly aflixed tothe lower end of the inner blade member 33, and the bifurcated portionof this member engages a pin 49 which serves to pivotally support theentire blade assemblage upon the main U-shaped support member I9. Asomewhat similar Y-shaped member 5I is affixed to the lower end of theouter blade member 35 and engages a pin 53 which serves to pivotallyinterconnect the outer blade member with one end of the links 39. Themember 41 is provided with a pair of upstanding portions 55, castintegral therewith. These members are positioned so as to form a bellcrank lever which is utilized for effecting the operation of the switch.

As is shown particularly in Figs. 2, 5, and '1, the disposition af thelinks 31 and 33 which connect the blade members at either end is suchthat the blades are skewed with respect to one another. 'I'hisarrangement makes possible an extremely rigid structure and adds much tothe reliability of operation of the device.

The switch actuating mechanism proper comprises a pair of offset crankmembers 51 and 59, and a pair of link members 6I and 63 which serve toconnect each of the crank members with one of the two blade members. Asmentioned above, the crank members are cast integral with each other inthe member I5 which is rigidly bolted to the cap portion II of therotatable insulator 1, and the .desired offset isobtained (see Fig. 2)by angularly displacing the holes for the associated pivot pins 65 andB1 which operatively connect the cranks with the link members BI and 63.Each of the link members engages its cooperating crank member, and theblade member which it is adapted to actuate through a universal joint69, which is capable of accommodating itself to the normal relativemovement of the several parts during the operation of the switch.

The quadrilateral linkage arrangement of the blade assemblage allows theouter blade member 35 to be moved longitudinal with respect to the otherblade member during the operation'of the switch, and through thearrangement of the offset crank members 51 and 59 and the other elementsof the actuating mechanism, the normal swingable motion of the entireblade assemblage is prevented, during the switch opening and during theswitch closing operation, while the desired nosas relative movement ofthe two biade members is being effected. By this means, the switchclosing and the switch opening operations are both caused to take placein two successive steps and, as will be described in some detail insubsequent paragraphs, the improved operation of the device is therebymade possible. The cranks El and 59 and the link members 6i and 63 whichserve to conneet the cranks to the associated blades form a pair oi'toggle linkages, each oi which is moved through its dead center positionduring the final stages oi the circuit closing operation. Through thisarrangement it is possible for the switch operating mechanism to exertextremely large iorces during the normal operation oi' the switchwithout unduly stressing the insulator columns or other parte oi thedevices.

The cooperating tooth portions 43 and 25 of the inner blade member 33and the contact law it are adapted to engage, during the switch closingoperation, in such manner that the two spaced insulators 3 and 5 arerigidly interconnected, thereby distributing any stresses to wl'iicheither insulator might be subjected equally between the two.V .d datplate member ll, which is rigidly bolted to the central insulator bserves to mechanically connect that insulator with the rotatableinsulator l, the base portion "it oi the cranlr assemblage l5, which iscircular in outline and mounted concentric with the axis of rotation oithe rotatable insulator "l, being adapted to eirtend through a suitableopening it iormed in the plate il in order to provide a bearing suriacetherewith. The other switch terminal di is bolted to the lower end oitheplate ll.

Llille combined effector mechanically interconnecting the'twospacedinsulators il and t by the blade assemblage i'l, and oi thenmechanically connecting those two vinsulators with the other end-crinetoggle actuating linkage by the plate member li, maires pssible analmost complete elimination of any cantilever stresses on the insulatorcolumns during the switch actuating operation. Danger of breakage oi theinsulators is thus reduced' to a' minimum'iand/the safety factor of theswitch is raised 'very considerably.

The switch is shown in the closed circuit position in Figs. i, 2 and t.To open the switch, the rotatable insulator l is turned in a countercloclrwise direction. This movement ediately causes the center oi thepivot pin tb which connects the outer linlr 6l .with the outer crani;member tl to be moved from the dead center position shown in Fig. 2 to aposition where it begins to eiiect a longitudinal pull upon the outerblade member it. The initial portion oi 'this rotatable movement has .noappreciable edect upon the other blade member 3i due to the iact thatthe center oi the pivot pin bl which connects the inner link bt with theinner cranlr member tu is being moved from an overcenter positionthrough the dead center position. Thus, the effect of the initialportion oi the switch opening operation is to move the outer blademember 35 longitudinally with respect to the inner blade ember 3b, whileholding that blade member and the blade assemblage as a wholesubstantially in the closed circuit position. The angular displacementoi the cranlrs and the arrangement oi the linkages are so correlated,with respect to one another', that sucient relative movement oi theouter blade member 3b is effected to produce a disengagement oi thecooperating contact surlaces db and lill ol the contact portion di andthe law i3, which s norlly lengage with a wiping action, and to move theouter ends ol the two blade meers sciently close togetherto edect theremoval of all pressure fro the cooperating toothed portions 4l and i5.This position is illustrated in Figs. 3 and 6.

As the opening operation progresses. the entire blade assemblage il issg out oi engagement with the jaw il, due to the lact that the passageci the center line of the pivot pin di, which connects the inner lint:tt to the lower cranlr inember bt, over the dead center position resultsin the producing oi' a tensioning force upon the parallel, opstandinglever portions tb which are formed integral with the support di ior theinner blade member, there upstanding portions acting substantially as abell cranlr lever. While a very slight amount oi relative movement olthe blade members di and iii may taire place during the remainingportions ci the circuit opening operation, the edect oi this movement isnegligible, and as the angularity between the center line ol the switchand the cranks increases, this relative movement becomes progressivelyless.

Figs. 3 and 6 illustrate the position oi the blade members immediatelyfollowing the movement oi the center oi the inner pin iii to the deadcenter position. it will be seen that the upper blade member has movedthe desired amount longitudinally with respect to the lower blademember. d li'ig. il illustrates the position ol the blade and linemembers at a subsequent position during the circuit opening operation.ln this view, the blade assemblage has been sg completely out oiengagement with the contact jaw.

11 en the switch is in the lull open circuit position, the bladeassemblage il is preierably moved to a substantially vertical position,this arrangement nimising the stresses upon the several portions oi theactuating mechanism.

During the switch closing operation, the rotatable insulator 'i is movedin a cloclrwise direction. The initial result ol' this movent is tocause the blade assemblage il to be sng irom the iull open circuitposition to a position where the outer end oi' each ol the individualblade ernbers is in pro t 111.1 to the contact law ii. .at this point,the toggle linlrage which is iormed by the inner cranlr member til andthe inner iinlrage member ti is adapted to be in the iully erstantiallyno swingable movement oi the inner blade member iii oi the bladeassemblage il is produced. liihe toggle inltage iormed by the outercranlr member lili and the outer linlr iii does not, however, reach theextended position as soon as the inner linlrage, simpatia-result, duringthe final portion ci the circuit closing operation, the outer blademember till 'is proved :longitudinally with respect to the inner blademember illiwhile that member is held substantially stationary.`

'This longitudinal movementvcauses the outer blade member-lib to movelaterally with respect to the inner blade member il by virtue oi' theuuadrilateral linlrage arrangement. The toothed embers it and ill arethus pushed into engagement with'each other, and the other contactportions il and iii are caused to engage with a high pressure wipingengageent.

When the switch is in the closed circuit position, the linlrs it whichpivotally ,loin the two blade chers at their outer ends are preierm ablyin a position which is at right angles to the axes of the blades, inorder that no force shall be exerted by the linkage biasing the switchin either direction. The inner toggle linkage, which effects theswingable movement of the blade assemblage, is in the overcenterposition when the switch is closed, and the rotatable insulator 'I ispreferably against a stop. This arrangement, and the positioning of theouter toggle linkage in substantially the extended position when theswitch is closed, serves to provide an effective means for latching theblade assemblage in the closed position.

Since the links 39 which pivotally Join the blade members at their outerends, are displaced some distance from the point of engagement of thecontact portions 4I with the jaw member I3, these links serve to form afulcrum point for each of the two blade members. Thus, as the outerblade 35 is moved longitudinally and laterally with respect to the otherblade 33 during the switch closing operation, the resilience of each ofthe blade members is utilized for resiliently biasing the cooperatingcontact portions of the switch into engagement with one another, eachblade acting in substantially the manner of a simple crowbar type lever.This arrangement greatly reduces the cost of the switch by allowingrigid contact portions to be utilized, and since a very considerablemovement of the blade members may take place without eiecting anysubstantial reduction in the contact pressure, the device is practicallyself-compensating for wear. If it is desired that one of the blademembers shall remain absolutely stationary while the other is beingmoved to effect the actuation of the contact pressure securing means, itis possible to introduce a small amount of play into the operatinglinkages. Ordinarily, however, any inaccuracies in manufacture or anyslight relative movement of the twov blades will be taken up by thenatural resilience of those members.

The main crank means, as is shown particularly in Figs. 2, 6 and '7, iscast with a pair of projecting lug members 19 which form a continuationof the inner crank portion 59 thereof. This is done in order that thepin 6l which connects the inner tie member 63 to the inner crank membermay be positioned at either side of the center line of the switch,thereby making it possible to operate the switch by rotating therotatable insulator 1 in either a clockwise or a counter clockwisedirection.

From the foregoing, it will be seen that I have disclosed the featuresoi' a new form of disconnecting switch wherein a high contact pressureis securedbetween the cooperating contact surfaces of the bladeassemblage and the contact means through the provision of a multipleblade structure, one of the blade members being movable relative to theother (or others) in order to effect the actuation of the Contactpressure securing means. Further, I have disclosed an improved operatingmechanism suitable for switches of this type which is provided with asingle rotatable actuating member, and means movable to successivelycause the blade assemblage to be swung from the open to the closedcircuit position and to then cause one of the blade members to be movedrelative to the other in order to effect the actuation of the contactpressure securing device.

My improvedl operating mechanism utilizes ,a pair of toggle linkages foreffecting the succes'- sive actuationy of the blade and the contactmeans, and it is so arranged that the movement of the blade assemblageand of the individual movable blade means is positively controlled atall times. Thus, any lateral movement ofthe blades which might tend toprevent the free movement of the switch to the closed circuit positionis positively prevented, and the need for any biasing means whatsoeveris eliminated. 'I'hrough this arrangement, the improved switch which Ihave disclosed is capable of operating equally Well in anyposition-vertically, horizontally or inverted.

In addition to the above, I have shown, in the preferred embodiment ofmy invention, how the novel principles disclosed may be utilized in aswitch which is comparatively inexpensive to manufacture despite itsgreat reliability in operation. Among the desirable features disclosedis the provision of an arrangement wherein the natural inherentresilience of the blades is utilized for biasing the cooperating contactsurfaces into engagement with one another, and an improved linkage andcrank assemblage which is extremely simple in design.

While in the foregoing description the various portions of the switchhave been specified as being mounted upon insulators, it is to beunderstood that the term insulator shall include insulators or anycombination of such devices into a column or the like. In the claimstheterm insulator column has been used, and it is my desire that thisshall include either a single insulator or a multiplicity of insulators.

In accordance with the patent statutes, I have disclosed, in theforegoing, the structural details of a preferred embodiment of myinvention. It is to be understood, however, that many of these detailsare merely illustrative, and the broad principles of the invention maybe applied to numerous other structures and to numerous devices otherthan disconnecting switches. It is my intention, therefore, that thelanguage of the accompanying claims shall be accorded the broadestreasonable interpretation, and that my invention shall be limited onlyby what is expressly stated therein and by the prior art.

I claim the following as my invention:

1. In an electric switch, a contact means, a pair of blade members forcooperating therewith,

at least one of said blade members being movable longitudinally withrespect to the other of said blade members during the operation of saidswitch, and actuating means for said switch, in cluding means operableduring the circuit closing operation to move both of said blade membersinto proximity with said contact means and to then move said one of saidblade members longitudinally relative to the other of said blademembers, said actuating means including means for positively determiningthe relative positions of said blade members at all times during theoperation of said switch.

2. In an electric switch, a single contact means, a pair of bladeAmembers for cooperating therewith, at least one of said blade membersbeing longitudinally movable relative to the other of said blademembers, and actuating means for said switch, including means operableduring the circuit closing operation to move both of saidblade membersinto proximity with said contact meansand to then move one of said blademembers longitudinally Vwith respect to the other oi said members,saidactuating means including rigid means for positively determining therela-l lli titl

liti

ausente tive positions oi' said blade mebers during the operation oisaid switch.

d. lin an electric switch, a single contact means, a pair oi blademembers ior cooperating therewith, one oi'" said blade melders beinglongitudinally and laterally movable relative to the other oi said blademembers, and actuating means tor said switch including means operableduring the circuit closing operation to move both oi said blade membersinto proirimity with said single contact means and to then move said oneoi said blade members longitudinally and laterally relative to the otheroi said blade members, said longitudinal' and said lateral movementcausing the cooperating contact portions oi said contact means and. saidblade members to be moved into intimate engagement with one another,said actuating means positively preventing substantial relativelongitudinally or lateral movement oi' said blade members except whenthose meinbers have been moved into proximity with said contact means.

f-i. lin an electric switch, a contact means, a

blade assemblage, including a pair oi blade meA bers, tor cooperatingwith said contact means, at least one oi said blade members beingmovable relative to the other oi said blade members, means lorsupporting said blade assemblage ior swingable movement trom oneposition to the other, and actuating means lor said switch iricludirgmeans operable during the circuit closing operation to swing said bladeassemblage into proximity with said contact means and to then move saidone oi said blade members relative to the other while the said otherblade member is held substantially stationary, said actuat-u ing meansincluding rigid means ior positively determining the relative positionsoi' said blade members at all times during thev operation oi saidswitch.

5. ln an electric switch, a contact jaw, a pair oi blade members, atleast one oi which is longitudinally and laterally movable with respectto the other, tor cooperating with said contact jaw, and actuating means:tor said switch, in-n cluding means operable during each circuitclosing operation to successively move said blade members into proximitywith said contact law, and to then move said one oil/said blade mem berslongitudinally and laterally relative to the Y other in order to eiiectan intimate engagement between the cooperating contact portions oi" saidjaw d said blade members, said actuating means positively preventingsubstantial, relative longitudinal or lateralmovement oi said blademembers except when those members have been moved into proaimity withsaid contact means.

d. in an electric switch, a single contact means, a pair oi' generallyparallel blade members, at least one oi which is longitudinally movablerelative to the other, i'or cooperating with said contact means, meansior' producing a high pressure engagement between the cooperatingcontact .airiaces oi said blade members and said contact means when saidswitch m in the closed circuit position, and actuating means lor 'saidswitch including a pair oi cranlr members, means :lor mechanicallyconnecting each oi said cr members to one oi said. blade members, and asingle rotatable means lor actuating both oi said cranlr. members saidcranlr mebers, said con-- neeting means, and said blade members being socorrelated that, during each switch uw operation, said blade members aremoved into promity to said contacteans thout sub@ sttial relativelotudinal ovement d are then moved longitudinally relative to one another to edect the actuation oi' said contact pressure securing means..

'l'. in an electric switch, a single contact means, a blade assemblage,including a pair or general-Il ly parallel blade members, iorcooperating with said contact means, at least one oi said blade membersbeing longitudinally movable relative to the other or said blademembers, mes i'or supporting said blade assemblage ior swingablemovement into and out oi engagement with said contact means, andactuating cans ior said switch including a separate operated linlrageior engaging each oi said blade mem bers and a single rotatable meansior actuating said linkages, said linkages and said rotatable meansbeing so correlated that, during each switch closing operation, saidblade assemblage is rst swung into proximity with said contact means,without substantial relative longitudinal movement oi said blademembers, and then, while the other oi said blade members is heldsubstantially stationary, said one oi said blade members is movedlongitudinally with respect to the said other blade member in order toei'- iect an intimate engagement between the cooperating contact portionoi.' said blade members and said contact means, said actuating meanspositively determining the relative positions oi said blade'members alltimes during the oper--v ation oi the switch.

o. in an velectric switch, a contact eans, a

pair oi blade members, at least one ol which is movable longitudinallyrelative to the other, for cooperating with said contact means, andactuating means tor said switch, inclu a separate toggle linlrage lorengaging each oi said blade members, said ges being adapted to be in thecollapsed position when said switch is in the normal open circuitposition and being adapted to be moved to the extended position, atdiderent times, rduring the switch closing operation, thereby causingboth oi said blade mebers to be moved substantially simultaneously intoproximity with said contact means and then causingsald one oi said blademembers to be moved longitudinally relative to the other blade mber inorder to eitect an intimate erigagernent between the cooperating contactportions oi saidblade members and said contact means.

d. in an electric switch, a contact means, a blade assemblage, includinga pair ci blade members ior cooperating, with said contact means, atleast one oi said blade members being movable longitudinally relative tothe other ci said blade members, means i'or supporting said bladeassemblage tor swingable motion, and actuating means tor said switch,including a separate toggle linlrage ior operatively engaging each oisaid blade members and a single rotatable means ior actuating both oisaid linlrages, both oi' said linkages being adapted to be in thecollapsed position when said switch is in the open circuit position andbeing movedtoward the extended position by said rotatable means duringthe closing operation oi' the switch, and one oi' said linlrages beingadapted, during the switch closing operation, to reach the iullyentended position beiore the other in order that said bla-de assemblagemay be sg to prorrty with said contact means during the tial,

stages oi' the switch closg operation and lli lid

btt

dit

blt

il il,

lili

held in that position while said one of said blade members is movedlongitudinally relative to the other, in order to eect an intimateengagement between the cooperating contact position of said blademembers and said contact means.

10. In an electric switch, a single contact means, a pair of blademembers, at least one of which is movable relative to the other, alinkage for connecting said blade members adjacent the end which engagessaid contact means, and actuating means for said switch, including meansoperable during each circuit closing operation to move both of saidblade members into proxunity with said contact means and to then move atleast one of said blade members longitudinally relative to the other ofsaid blade members, said relative longitudinal movement of said blademembers, effecting the actuation of said linkage and thereby producingan intimate engagement between the cooperating contact surfaces of saidblade members and said contact means, said actuating means includingmeans for positively determining the relative positions of said blademembers at all times during the operation of said switch.

11. In an electric switch, a contact means, a pair of blade members forcooperating therewith, at least one of said blade members beinglongitudinally movable relative to the other of said blade members,means, including a link member pivotally joined to each of said blademembers adjacent the end which engages said contact means, for causing ahigh pressure engagement between the cooperating surfaces of said blademembers and said contact means when said switch is in the closed circuitposition, and actuating means for said switch, including means operableduring each circuit closing operation to move both of said blade membersinto proximity with said contact means and to then move one of saidblade members longitudinally relative to the other of said blademembersin order to elect the actuation of said pressure securing means, saidactuating means including rigid means for positively determining therelative positions of said blade members at all times during theoperation of said switch.

12. I n an electric switch, a unitary contact means, a blade assemblage,including a pair of blade members, for cooperating with said-contactmeans, at least one of said blade members being movable relative to theother of said blade members, means for supporting said blade assemblagefor swingable movement from one position to another, means, including alink member pivotally joined to each of said blade members adjacent theend which engages said contact means, for causing a high pressureengagement between the cooperating surfaces of said blade members andsaid contact means when said switch is in the closed circuit position,and actuating means for said switch including means operable during thecircuit closing operation to swing said blade assemblage into proximitywith said contact means and to then move said one of said blade membersrelative to the other, while the said other blade member is heldsubstantially stationary, in order to elect the actuation of saidpressure securing means, said actuating means positively determining therelative positions of said blade members at all times during theoperation of said switch.

13. Inan electric switch, a unitary contact means, a pair o! blademembers for `cooperating therewith, at least one of said blade membersbeing longitudinally movable relative to the other of said blademembers, means, including a link member pivotally joined to each of saidblade members adjacent the end which engages said contact means, forcausing a high pressure engagement between the cooperating surfaces ofsaid blade members and said contact means when said switch is in theclosed circuit position, and actuating means for said switch including aseparate linkage for engaging each of said blade members, said linkagesbeing so correlated that, during the switch closing operation, saidblade members are moved substantially simultaneously into proximity withsaid contact means and then said one of said blade members if movedlongitudinally relative to the other of said blade members in order toeffect an intimate engagement between the cooperating contact portionsof said blade members and said contact means.

14. In an electric switch, a unitary contact means, a blade assemblage,including a pair of blade members, for cooperating with said contactmeans, at least one of said blade members being longitudinally movablerelative to thev other of said blade members, means for supporting saidblade assemblage for swingable motion, means, including a link memberpivotally joined to each of said blade members adjacent the end whichengages said contact means, for causing a high pressure engagementbetween the cooperating surfaces of said blade members and said contactmeans when said switch is in the closed circuit position, and actuatingmeans for said switch including a separate, crank operated linkage forengaging' each of said blade members and a common rotatable means foractuating said linkages, said linkages and said rotatable means being socorrelated that, during each switch closing operation, said bladeassemblage is swung into proximity with said contact means, withoutsubstantial relative movement of said blade members, and then, while theother of said blade members is held substantially station ary, said oneof said blade members is moved longitudinally with respect to the saidother blade member in order to eifect the actuation of said pressuresecuring means.

15. In an electric switch, a pair of spaced insulator columns,conducting means mounted on each of said columns, a movable bladeassemblage, including a pair of blade members, for bridging saidconducting means to provide an electrical circuit therebetween, andactuating means for moving said blade assemblage to the open and to theclosed circuit position, said blade assemblage and said conducting meansincluding cooperating means operable to rigidly interconnect saidinsulator columns so as to prevent relative movement therebetween duringat least a portion of the circuit closing operation, at least one ofsaid blade members being movable longitudinally relative to the otherduring the circuit closing operation to effect the operation of saidinterconnecting means, said actuating means including means operableduring the circuit closing operation to move both of said blade membersinto proximity with said contact means and to then move said one of saidblade members longitudinally relative to the other of said blademembers, said means positively ydetermining the relative positions ofsaid blade members at all 'times during the operation of said switch.

16. in an electric switch, a pair of spaced insulator columns,conducting means mounted on each of said columns, a movable bladeassemblage, including a pair of blade members, -ior bridging saidconducting means to provide an electrical circuit therebetween, andactuating means for moving said blade assemblage to the open and to theclosed circuit position, said blade assemblage and said conducting meansincluding cooperating toothed members, capable of accommodatingthemselves to a considerable amount of relative movement of saidinsulator columns, for rigidly interconnecting said insulator columns soas to prevent relative movement therebetween during at least a portionof the circuit closing operation, at least one of said blade membersbeing movable relative to the other, during the circuit closingoperation to eiect the engagement of said cooperating toothed members,said actuating means including means operable during the circuit closingoperation to move both of said blade members into proximity with saidcontact means and to then move said one of said blade members relativeto the other of said blade.

members, said means positively determining the relative positions ofsaid blade members at all times during the operation of said switch.

l'l'. In an electric switch, a pair of spaced insulator columns,conducting means supported upon one of said columns, a blade assemblage,means for supporting said blade assemblage upon the other of saidcolumns for swingable movement into and out of engagement with saidcontact means to close and to open the electrical circuit through saidswitch, and actuating means for moving said blade assemblage to the openand to the closed. circuitposition, said blade assemblage and saidconducting means including cooperating means operable to rigidlyinterconnect said insulator columns so as to prevent relative movementtherebetween during at least a portion of the circuit closing operation,at least one of said blade members being movable relative to the otherduring the circuit closing operation to effect the operation of saidinterconnecting means, and actuating means for said switch including aplurality ci cooperating linkages so arranged and so correlated that,during 'the switch closing operation, said blade assemblage is swunginto proximity with said contact means and then said one of said blademembers is moved relative to the other of said blade members in order toeffect the operation of said interconnecting means, said linkagespositively determining the relative positions of said blade members atall times during the operation of saidswitch.

18. In an electric switch, a contact means, a blade assemblage whichincludes a pair of blade members and which is movable between twoextreme positions for cooperating therewith, at least one of said blademembers being movable longitudinally relative to the other blade memberduring the operation oi said switch, and actuating means for saidswitch, including means operable successively to move said bladeassemblage from one position to the other and to then cause relativelongitudinal movement between said blade members, said actuating meanspositively controlling the movement of said blade assemblage and therelative positions of said individual blade members at all times, inorder that the movement of said blade assemblage and the relativemovement of said blade members shall take place in successive steps.

19. In an electric switch, a contact means, a blade assemblage,including a pair of blade mem-u bers, for cooperating with said Contactmeans, at least one of said blade members being movable longitudinallyrelative to the other of said blade members, means for supporting saidblade assemblage for swingable movement into and out oi engagement withsaid contact means, and actuating means for said switch including meansoperable successively to swing said blade assemblage from one positionto the other and to then move said one of said blade members longitudinally relative to the other, said actuating means positively determiningthe relative positions oi' said blade members at all times during theoperation of said switch.

MRBERT J. CRABBS.

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